Stencil brush



STENC IL BRUSH.

Grginal Filed Deo. 13. 1930 2 Sheets-Sheet @sa 279 i932, J. FLQCKHARTSTENC IL BRUSH Original Filed Deo. 13, 1930 2 Sheets-Sheet INVENTOR;JAMES FLOCKHART ATTORNEY.

Patented Dec. 27, 1932 liiatTED STATES PATENT OFFICE s'rENoIL BRUSHApplication led December 13, 1930, Serial No. 502,112. Renewed Hay 24,1932.

riihis invention relates to improvements in stencil brushes and moreparticularly to ink spreaders for screen stencil machines.

Among the objects of the invention are to accomplish uniform feedingdistribution and penetration of the ink or color substances through thestencil.

Other objects are to provide an ink fountain and spreader that isautomatic in action 0 and which may be synchronized "with the otherfunctions of screen printing machines actuated by power.

A further object is to accomplish a double spreading action with eachinking operation of the brush.

Other objects and advantageswill appear as the description progresses.

Reference is here made to my copending applications as follows, forfurther particulars: Fountain brush, Ser. No. 396,082, filed Sept. 30.1929, stencil printing machine, Ser. No. 429,337. tiled Feb. 18, 1930,and applications to be filed contemporaneously with this application,entitled Stencil brushes and screen printing machines.

In this specification and the accompanying drawings the invention isdisclosed in its preferred form'. But it is to be understood that it isnot limited to this'form because it may be embodied in other forms. i Itis also to be understood that in and by the claims following thedescription it is desired t0 cover the invention in whatsoever form itmay be embodied.

ative mechanisms.

Fig. 2 is aplan view from above, of the same.

Fig. 3 is a vertical section of the stencil brush taken on the lineIlI-i-III, Fig. 1, shown in the operative position on the inking andspreading stroke. I

Fig. 4 is a similar view shown in the return stroke with the fountainclosed and the second spreader in operation.`

Fig. 5 is a full side elevation of the same, as shown in Figs. 1-2.

In detail the construction illustrated in the drawings, referring toFigs. 1-2 comprises the sides 1 and 2 of the swing frame prlntlngmachine. The reciprocating crosshead a is guided in slots in these Sidesand 5' is adapted to pass back and forth above the screen stencil 4,stretched taut on the screen frame 5.I The screen frame is adjustablyheld in the swing frame 1-2, by the screws 6.

The crosshead has the slotted brackets 7-7 thereon which engage thetransverse push rod 8, which synchronizes the movement of the crossheadwith the rise and fall of the swing frame 1 2.

The pivot rod 9 is mounted in the brackets 65 10-10, also fixed on thecrosshead 3. The rod 9 moves in unison with the crosshead 3; whereas thepush rod 8 stops and starts in synchronism with the frame 12, because ofthe'E slots 7 in the brackets 7 7, as will 7o be hereinafter more fullydescribed.

Referring to Fig. 5, the ink fountain brush consists of the front plate11-11 having the ends 12-12. The upper portions of the ends 12-12 arepivoted on the 75 rod 9. These ends 12 are also provided with the hooks13-13 engaging the push rod 8. The rear plate 14 fits slidably betweenthe ends 12.-12, but snugly enough to confine the ink X within the cupformed by the curved plate 11. This plate 14 has the lugs 15-15 pivotedon the rod 9. In the closed position, shown in Fig. 4, the plate 14abuts the crosshead 3.

The lower edges of the plates 11-14 contact in the closed position toform a gate at 16, between the spreaders 1'Z-18, respectively fixed inthe lower edgesA of the plates 11-14. These spreaders or brushes arepref 90 erably set at an angle of approximately 60 to the plane of thescreen 4. This angle is about the angle best adapted to the spreading ofheavy inks and enamels such as are used in this art. I have discoveredthat heavy pressure and squeegee-like action is not desirable inattaining the highest development of screen stencil impressions. Asingle piece of heavy soft leather. beveled as shown, or severalthicknesses of thin leather in lamithe screen stencil.

' brackets 10--10. Y

nated formation, have proved the best material for the spreaders.

i Normally the swing frame 1-2 is elevatn ed on its pivot, not shown,with the fountain brush in the closed position, as in Fig. 4, due to thepull of the rod 8. Upon the lirst phase of the operation of the machine`the rod 8 is pushed forward as is showil in Fig. 3. As the rod 8 has afree engagement with the crosshead 3 due to the slots 7', the body 11-12of the brush is swung on the pivot 9 to open the fountain at 16, seeFig. 3. The brackets 7-7 are then engaged by the movement of the rod 8and the frame 1-2 is low-V ered. The continuation of the stroke spreadsthe ink X across the screen 4, ahead of the spreader 18, whichdistributes it evenly, and brushes or rubs it gently through the screenstencil.

The initial portion of the return stroke, Fig. 4, causes the rod 8 topull on the hooks 13-13, to close the gate 16. which pushes the plate 14against the crosshead 3 and rotates the ink assembly on the rod 9. Thiselevates the spreader 18, and brings the spreader 17 into operativeposition on the screen 4. The continued pull of the rod 8 causes it toengage the brackets 7'-7. and return the inking mechanism to thestarting position. During the return stroke the spreader 17 forces thesurplus ink X through The end of the stroke of the rod 8 again pulls theswing frame 1-2 into the elevated position with the ink gate 16 closed,during the operation of removingr andreplacing the impression sheetbeneath e th'e stencil.

The operation has been described as in a power operated machine. Itisobvious, how ever, that the crosshead 3 may be operated by `manuallypushing and pulling the rod 8, or otherwise applying movement to theplate 11. The friction of the spreader 18 on the screen 4 causes it tolag while the plate 11 moves away from -it to open the gate 16.

The quantity of ink fed is regulated by means of the screw 19, threadedin the plate 11 and engaging the plate 14. This screw 19 may be set upto entirely7 close the gate 16, while the fountain brush is beinginstalled or removed from the machine. which is readf ily done byreleasing the setscrews 21)-20 and Ql-Ql to release the rod 9 from theWhen not in use the brush will stand upright on the spreaders 17-18.

To insure the operation of the rod 8 in the slots 7 7. as described. itis desirable to apply a definite frictional resistance in the operationof the crosshead 3. This is simply accomplished by splitting thecrosshead guides 3-3 and screws 21-21. see Fig. 5. so that they arefrictionallv retarded in their respective grooves S22-22 in the sides1-2.

The transverse slits S23-23 extending upsnreading them byy the ward intothe body of the spreaders l7-18, see Figs. 1-2, render them moreadaptable to inequalities in the plane of the material upon which thestencil impression is being made. These slits are made in laterally od'-set or break joint relation in the respective sprcaders, so that any inkleaking through one spreader will be distributed by the tollowingspreader.

Thus slitting the spreaders is especially advantageous in making stencilimpressions upon leather and other uneven surfaces and in compensatingfor uneven adjustments of the screen frame with respect to the platenwith which the screen 4 cooperates. These slits in eli'ect create aplurality7 of longitudinally alined spreaders, whether used singly or inpairs, as shown.

Havingr thus described this invention, what I claim and desire to secureby Letters Patent is:

1. A stencil brush including a front plate having enclosing ends; a rearplate pivoted between said ends and meeting the lower end of said frontplate to form an ink fountain; spreaders in the lower edges of each ofsaid plates respectively.

2. A stencil brush including a front plate having enclosing ends; a rearplate pivoted between said ends, the lower edges of said plates meetingat an angle to each other; spreaders in the lower edges of each of saidplates respectively, on opposite sides of said meeting edges.

3. A stencil brush including a pair of divergi'ng plates pivotedtogether and meeting near their lower edges and adapted to form an inkfountain; and spreaders fixed in the lower edges of said plates, at anangle to the perpendicular, adjacent said meeting edges.

4. A stencil brush including a pair of diverging plates pivoted togetherand meeting near their lower edges and adapted to form an ink fountain;supporting means engaging said pivot; means for moving said platesrelatively to each other; and spreaders at the lower end of both of saidplates.

5. A stencil brush including a pivot rod guided in a frame; a pair ofplates pivoted on said rod and adapted to form an ink fountain; preaderslixed in the lower edges of said plates; and means for moving said pivotrod back and forth and moving said plates relative to each other.

6. A stencil brush including a reciprocat ing mechanism having a pivotrod thereon; an actuating mechanism having a delayed engagement withsaid reciprocating mechanism; a. pair of plates pivoted on said pivotrod and meeting near their lower edges and adapted to form an inkfountain, one of said plates engaging said actuating mechanism; andspreaders fixed in said plates respectively, on opposite sides of saidmeeting edges.

7. A stencil brush including a front plate having enclosing ends; a rearplate pivoted between said ends and meeting the lower end of said frontplaie to form an ink fountain;

spreaders having: transverse splits therein, in

the lower edges of each of said plates, respectively. I

In testimony whereof I have hereunto set my hand this 5th day ofDecember, 1930.

JAMES FLGCKHART.

